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Review Paper
Effects of psychosocial work factors on preterm birth: systematic
review and meta-analysis
H.A. Adane
a
,
c
,
*
, R. Iles
a
, J.A. Boyle
b
, A. Gelaw
a
, A. Collie
a
a
Healthy Working Lives Research Group, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
b
Eastern Health Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
c
Department of Public Health, College of Medicine and Health Sciences, Wolkite University, Wolkite, Ethiopia
article info
Article history:
Received 27 July 2023
Received in revised form
30 October 2023
Accepted 4 December 2023
Keywords:
Psychosocial job strain
Preterm birth
Occupational exposures
Pregnant women
Meta-analysis
abstract
Objectives: Preterm birth is one of the global public health issues that result in high rates of infant
mortality and long-term health complications. We sought to explore the association between psycho-
social work factors and preterm birth.
Study design: Systematic review and meta-analysis.
Methods: This systematic review and meta-analysis searched relevant literature from electronic data-
bases to explore the association between psychosocial work factors and preterm birth. The methodo-
logical quality of the included studies was evaluated through the Joanna Briggs Institute's critical
appraisal method. We performed a meta-analysis using a random-effects model to combine odds ratios
(ORs) from studies with similar definitions of exposure and outcome. The quality of the evidence was
evaluated using the GRADE (Grade of recommendation, Assessment, development, and Evaluation)
method to assess.
Results: Ten studies were included, with a total of 92,815 participants. Moderate evidence indicated a
positive association between high psychosocial job strain and preterm birth. The result from the meta-
analysis supported the statistical significance of this relationship (OR 1.32 [95% CI (1.22e1.44)]).
Conclusions: Pregnant women who experience high levels of psychosocial job strain are more likely to
give birth prematurely. In order to decrease this risk, employers should prioritise creating supportive
work environments, government bodies should enact protective policies and regulations, and clinicians
should give advice to pregnant working women. Pregnant women should be aware of the risk of preterm
birth from psychosocial work factors.
©2023 Published by Elsevier Ltd on behalf of The Royal Society for Public Health.
Introduction
Preterm birth (PTB) is the birth of a baby before 37 weeks of
pregnancy.
1
It is a global health concern, with over 15 million ba-
bies born preterm each year.
2
Southern Asia and Sub-Saharan Africa
have the highest rates of PTB, accounting for over 60% of global
cases.
3
PTB can cause mortality and lifelong health problems.
4
One
million children under the age of 5 years die each year from PTB.
5
Significant disparities in PTB survival rates exist between low-
and high-income countries, with up to 90% mortality for babies
born <28 weeks in the former and only 10% in the latter.
6
There are many factors that can contribute to PTB, including the
mother's medical-related factors, genetics, lifestyle factors, envi-
ronmental exposure, and occupational hazards.
7,8
A growing body
of research indicates psychosocial hazards in the workplace, such as
job strain, organisational injustice, effort-reward imbalance, and
workplace violence, can increase the risk of poor pregnancy out-
comes.
9e11
Work-related psychosocial factors, hereafter called
‘psychosocial work factors’, are aspects of work that can have a
negative impact on workers' health, work performance, and job
satisfaction. These factors can include the work environment,
organisational conditions, and workers individual characteristics.
12
These factors have been shown to impact maternal health, with
potential effects on pregnancy outcomes.
13e15
The evidence suggesting a link between that psychosocial work
factors and PTB is inconsistent due to several methodological is-
sues, such as small sample size, different research designs, low
*Corresponding author. Monash University 553 St Kilda Road Melbourne, VIC
3004, Australia. Tel.: þ61456309546.
E-mail address: haimanot.adane@monash.edu (H.A. Adane).
Contents lists available at ScienceDirect
Public Health
journal homepage: www.elsevier.com/locate/puhe
https://doi.org/10.1016/j.puhe.2023.12.002
0033-3506/©2023 Published by Elsevier Ltd on behalf of The Royal Society for Public Health.
Public Health 228 (2024) 65e72
response rate, failure to consider potential confounding factors, and
measurements of psychosocial work-related factors.
16e19
Under-
standing the associations between work stress, job demands, work-
life balance, and other psychosocial factors, and their subsequent
influence on PTB is essential for better informing policymakers,
employers, and healthcare providers in reducing this adverse
outcome.
To date, no systematic review and meta-analysis has investi-
gated the effect of psychosocial work factors on PTB, underscoring
the need for a comprehensive review. This systematic review and
meta-analysis aimed to address this need by evaluating the avail-
able evidence and providing an enhanced understanding of psy-
chosocial work factors' influence on PTB. The research could lead to
evidence-based PTB prevention strategies worldwide, reducing
social, healthcare, and economic burdens. Investing in research to
improve care for preterm babies is essential to reduce the number
of newborn deaths worldwide and to achieve the Sustainable
Development Goals (SDGs) by 2030.
20
Specifically, SDG 3.2 aims to
reduce the global neonatal mortality rate to less than 12 deaths per
1000 live births.
20
Research in this area can also provide valuable
insights to inform future research, clinical practice, and policy
formulation. This can ultimately lead to better health outcomes for
both mothers and infants.
Methods
Design and protocol registration
This systematic review adhered to Preferred Reporting Items for
Systematic Reviews and Meta-analysis guidelines,
21
and the pro-
tocol was registered in PROSPERO (No: CRD42023409393).
Search strategy and eligibility criteria
We searched five electronic databases and reviewed reference
lists to find relevant studies. We combined MeSH and keywords
using Boolean operators (see Supplementary Table 1). The popu-
lation for this study was pregnant women who worked in paid jobs
throughout their pregnancy, and the exposure was psychosocial
work factors. Psychosocial work factors are defined on the basis of
three validated and recognized theoretical models: the demand-
control-support (DCS) model, the effort-reward-imbalance (ERI)
model, and organisational injustice (OJ) models and other mea-
sures of work-related stress. Psychosocial work factors, such as job
strain, were defined as the combination of high job demands, low
job control, and low social support at work,
21e23
effort-reward
imbalance or organisational injustice. The latter occurs when the
rewards obtained do not match the efforts invested by an
employee
24,25
or organizational injustice pertains to the perception
of unfairness in workplace rules, resource distribution, procedures,
and interpersonal relationships.
26
The main outcome of interest
was PTB, babies born alive less than 37 weeks of pregnancy. This
systematic review and meta-analysis included studies with obser-
vational (prospective, retrospective, caseecontrol, or cross-
sectional) or interventional designs. We excluded grey literature,
reviews, case studies, qualitative studies, editorials, commentaries,
conference abstracts, and non-English publications.
Study selection
The results of the literature search were imported into Covi-
dence, a software program that helps researchers to conduct sys-
tematic reviews efficiently.
27
Two reviewers (HAA and AG)
independently screened the titles, abstracts, and full texts of the
identified studies for eligibility. Any disagreements were resolved
through discussion.
Risk of bias assessment
The Joanna Briggs Institute Critical Appraisal tool was used to
assess the risk of bias (ROB),
28
while tools for methodological
quality varied by study design. Cross-sectional studies had eight
items, caseecontrol studies had 10 items, cohort studies had 11
items, and randomised control trials had 13 items. Responses for
each item were categorised as ‘yes’or ‘no’,‘unknown’or ‘not
applicable’. A study was deemed to have a high ROB if more than
70% of responses were marked as ‘yes’, a moderate ROB if between
50% and 69% of responses were marked as ‘yes’, and a low ROB
<50%.
29
Two reviewers (HAA and AG) independently assessed the
methodological quality of the studies, and a third reviewer (RI) was
consulted to resolve any discrepancies.
Data extraction
We extracted the required information, including study char-
acteristics (authors, publication year, geographic location, study
design and period) and participant characteristics (sample size,
population, exposure description) from each eligible study. We
recorded effect size with confidence intervals, adjusted variables,
and key results of the studies.
Data analysis
The key characteristics and main findings of each study are
summarised in Table 1. A random-effect model meta-analysis was
conducted using Stata (version 18). Study characteristics were
sought for subgroup analysis, and I
2
statistics were used to assess
heterogeneity. Odds ratios were converted to natural logarithms
and standard errors for meta-analysis. Additionally, a sensitivity
analysis was conducted to assess how the results might be influ-
enced by the risks of bias in the included studies.
Certainty assessment/Evidence quality
Evidence quality was assessed using the GRADE system, with
ratings of high, moderate, low, and very low.
30
The initial level of
certainty can be downgraded or upgraded based on eight pre-
defined criteria. Evidence was downgraded when two of the five
downgrading criteria were met. The ROB was considered serious if
over 50% of the studies demonstrate ROB (based on study-level ROB
assessment). Imprecision was classified as serious if more than 50%
of the eligible studies failed to meet the optimal information
criteria (OIS; sample size is small [<400 patients]). In cases where
OIS was achieved but the 95% confidence interval did not overlap
with any effect, it was also considered serious. An inconsistency
was considered serious if over 50% of the eligible studies exhibited
significant variation in effect estimate. Indirectness was deemed
serious if over 50% of the eligible studies exhibited significant
variation in the population, exposure, or outcomes examined.
Publication bias assessment was omitted due to the lower power of
funnel plot asymmetry tests with fewer than 10 studies. However,
publication bias was assessed as serious when more than 50% of the
studies derived from numerous small studies, with a predominant
proportion of them being commercially funded. Certainty assess-
ment was upgraded with large effect size, or doseeresponse rela-
tionship or the presence of counteracting plausible residual bias.
31
Following the GRADE method, practical messages were generated.
High certainty yielded ‘strong recommendation’, moderate cer-
tainty yielded ‘practice consideration’, while evidence levels below
H.A. Adane, R. Iles, J.A. Boyle et al. Public Health 228 (2024) 65e72
66
Table 1
Details of included studies.
Author (Year), Country Study design, data
collection period
Exposure of interest and
exposure measurement
Study population and
sample size
Time of exposure
measure
Proportion of women
engaged in high job strain
Outcome of interest and
proportion of women
who gave PTB
Main finding
Brandt et al. (1992),
35
Denmark
Caseecontrol, 1983
e1985
Job strain, evaluated
using Karasek's job strain
scale via mailed
questionnaire
Commercial and clerical
female workers
(N ¼1727)
After child birth with
recall period of 2.5e4.5
years
29.76% PTB ¼delivery before 36
weeks of gestation
(P¼34.98%)
High psychosocial job
strain was not associated
with PTB (AOR 1.03; 95%
CI: 0.77e1.39)
Breet et al. (1997),
36
USA Caseecontrol, 1988
e1991
Job strain, evaluated
using Karasek's job strain
scale through interview
African American and
Caucasian (N ¼398)
After 6 months of child
birth
35.43% PTB ¼babies born before
37 completed weeks
(P¼36.18%)
High psychosocial job
strain was associated
with PTB among African
American women (AOR
1.80; 95% CI: 1.1e3.1),
whereas no association
was found for Caucasian
Ceron-Mireles et al.
(1996),
16
Mexico
Cross-sectional, 1992 Job strain, evaluated
using Karasek's job strain
scale via interview
General population
(N ¼2429)
Immediately after
childbirth
21.74% PTB ¼birth prior to 37
weeks of gestation
(P¼11.28%)
High psychosocial job
strain was not associated
with PTB (COR 1.16; 95%
CI: 0.90e1.50)
Croteau et al. (2007),
37
Canada
Caseecontrol, 1997
e1999
Job strain, evaluated
using Karasek's job strain
scale via interview
General population
(N ¼5732)
Within 32 days of
childbirth
25.19% PTB ¼birth before 37
completed weeks of
pregnancy (P¼17.25%)
High psychosocial job
strain combine with low
support during
pregnancy was associated
with PTB (AOR 1.30; 95%
CI: 1.00e1.50)
Escrib
a-Agüir et al.
(2001),
17
Spain
Caseecontrol, 1994
e1995
Job demand, evaluated
using job demand model
via interview
General population
(N ¼576)
2 days after delivery 20.83% PTB ¼birth occur
between 22 and 36
completed weeks of
gestation (P¼39.58%)
High job demand was not
associated with PTB (AOR
1.5; 95% CI: 0.95e2.26)
Henriksen et al. (2010),
32
Denmark
Prospective, 1989e1991 Job strain, evaluated
using Karasek's job strain
scale via self-
administered
General population
(N ¼3503)
16th and 30th weeks of
gestation
24.89% PTB ¼birth prior to 37
completed gestational
weeks (P¼7.01%)
High psychosocial job
strain was not associated
with PTB (AOR 1.3; 95%
CI: 0.7e2.2)
Homer et al. (1990),
33
USA
Prospective, 1979e1983 Job strain, evaluated
using Karasek's job strain
scale via job title
General population
(N ¼772)
Job title during pregnancy 33.94% PTB ¼birth before 37
completed weeks of
pregnancy (P¼3.4%)
High psychosocial job
strain was associated
with PTB in women who
lacked motivation to
continue working (RR
8.40; 95% CI: 1.4e50.2)
Larsen et al. (2013),
18
Denmark
Prospective, Not stated Job strain, evaluated
using Karasek's job strain
scale through interview
General population
(N ¼51,265)
12the14th weeks and
30the32nd weeks of
gestation
15.36% PTB ¼birth before 37
completed gestational
weeks (P¼4.63)
High psychosocial job
strain was not associated
with PTB (AOR 1.39; 95%
CI: 0.86e2.23)
Meyer et al. (2007),
19
USA Cross-sectional, 2000 Job strain, evaluated
using Karasek's job strain
scale via job title
General Population
(N ¼21,773)
Job title during pregnancy 23.46% PTB ¼birth prior 37
completed pregnancy
weeks (P¼8.44%)
High psychosocial job
strain was associated
with PTB (AOR 1.17; 95%
CI: 1.00e1.36)
Vrijkotte et al. (2021),
34
Netherland
Prospective, 1997e1999 Job strain, evaluated
using Karasek's job strain
scale via self-
administered
General population
(N ¼4638)
12th weeks of gestation 6.81% PTB ¼birth before 37
completed gestational
weeks (P¼3.26)
High psychosocial job
strain was not associated
with PTB (AOR 1.39; 95%
CI: 0.86e2.23)
AOR: adjusted odds ratio; CI: confidence interval; COR: crude odds ratio; JDC: job demand control; PTB: preterm birth; USA: United States of America.
H.A. Adane, R. Iles, J.A. Boyle et al. Public Health 228 (2024) 65e72
67
moderate indicated insufficient guidance from scientific literature
for policymakers, clinicians, and patients.
Results
Search results
The comprehensive search found 2600 studies. After removing
duplicates, we screened 1631 studies based on their titles and ab-
stracts. Of these, 1578 studies were excluded, leaving us with 53
full-text articles for further review. After a thorough full-text re-
view, we excluded an additional 43 studies. As a result, 10 studies
met our inclusion criteria for this review (see Fig. 1).
Study characteristics
There were two cross-sectional,
16,19
four cohort,
18,32e34
and four
caseecontrol design studies.
17,35e37
These studies were published
between 1992 and 2021 and were conducted in high-income
countries. There were three studies conducted in the USA,
19,33,36
three in Denmark,
18,32,35
and one each in Canada, Mexico, the
Netherlands, and Spain.
16,17,34,37
The included studies involved
92,813 participants, and sample sizes varied between 398
36
and
51,265
18
participants (see Table 1).
The majority of studies used data obtained from self-report
methods, involving telephone or face-to-face interviews and
mail surveys, conducted before delivery in five studies
16,17,35e37
and after delivery in three studies.
18,32,34
The Karasek job-
demand-control scale was the most commonly used measure of
psychosocial work factors in this systematic review and meta-
analysis, with nine studies using it.
16,18,19,33e37
A single study
used a different measure, but the specific measure was not
specified.
17
In this systematic review of 10 studies, 12,617 par-
ticipants had high job strain and 42,780 had low job
strain.
16e19,32e37
Participants were interviewed during preg-
nancy,
18,33,34
in the immediate postpartum period (within the
first 6 weeks after childbirth),
16,17,37
and during the extended
postpartum period (within the first 12 months after giving
birth).
35,36
In two studies,
19,33
job title was used as a surrogate
measure of exposure, presenting an alternative means of
assessing exposure in those specific instances.
Outcome
In the systematic review and meta-analysis, most studies
identified PTB using administrative data, such as hospital records,
registers, or birth certificates.
16e19,33e37
However, one study used
self-reported data to identify PTB.
33
With the exception of one
Fig. 1. Procedure of selecting studies for systematic review.
H.A. Adane, R. Iles, J.A. Boyle et al. Public Health 228 (2024) 65e72
68
study,
35
the remaining studies used the PTB definitions set forth by
the World Health Organization.
16e19,32e34,36,37
Methodological risk of bias assessment
Five studies had low ROB,
19,32,34,36,37
two studies had moderate
ROB,
33,35
and three studies had high ROB.
16e18
All studies, except
one,
16
adequately addressed and controlled for potential con-
founding factors.
17e19 ,32e37
Maternal education (N ¼9),
17e19 ,32e37
smoking (N ¼9),
17e19 ,32e37
maternal age (N ¼7),
17e19,34e37
and
parity (N ¼6)
17,18,32,34,35,37
were the most frequently adjusted
variables across the studies (see Supplementary Table 2).
Summary of evidence gaps
This systematic review and meta-analysis identified several
gaps in the existing literature. First, there are 10 studies in high-
income countries and none in low-income countries.
16e19,33e37
Additionally, the majority of the included studies were retrospec-
tive in nature, which limits the ability to establish a causeeeffect
relationship.
16,17,19,35e37
Only four prospective studies were iden-
tified, which provide stronger evidence but are still relatively
scarce.
18,32e34
Furthermore, the review found that the studies were
predominantly outdated, collecting data in the late 20th century
and published in the early 21st century.
16,17,32,33,35e37
Moreover, the
review noted that all of the included studies focused solely on the
relationship between psychosocial job strain and PTB while
neglecting other important psychosocial work factors such as
organisational injustice, effort and reward imbalance, workplace
bullying and harassment.
16e19,32e37
Certainty of evidence and GRADE
The certainty of evidence concerning the association between
psychosocial job strain and PTB was found to be moderate, as
indicated in Supplementary Table 3. All studies included in the
analysis were observational, leading to an initial low-certainty
assessment. Certainty of evidence remained unaffected by ROB,
imprecision, inconsistency, indirectness, and publication bias,
while an upgrade occurred due to plausible residual confounding.
Publication bias
In this systematic review and meta-analysis, we conducted an
assessment for publication bias using Egger's regression test. The P-
value of the test was non-significant (P¼0.411), which indicates
that there is no statistical evidence for publication bias.
Psychosocial job strain and preterm birth
Ten studies investigated the association between psychosocial
job strain and PTB.
16e19,32e37
Four of seven low ROB studies
conveyed a significant positive relationship between psychosocial
job strain and PTB.
19,33,36,37
However, the remaining three low ROB
and three high ROB studies did not show a statistically significant
association between psychosocial job strain and PTB.
16e18
Eight studies, which had consistent definitions of outcome and
exposure, were included in the meta-analysis. The meta-analysis
(Fig. 2) showed moderate evidence supporting a positive associa-
tion between high psychosocial job strain and PTB. The combined
effect estimate derived from these studies was statistically signifi-
cant, with a value of 1.32 (1.22e1.44) (see Fig. 2).
Subgroup analysis
A subgroup analysis was conducted to identify potential sources
of heterogeneity. The effect estimate of high psychosocial job strain
on PTB was 1.32 (1.22e1.44) in all subgroups, with no significant
heterogeneity (I
2
¼0.0%, P<0.901) (see Table 2).
Sensitive analysis
Sensitivity analyses were performed with studies that had low
ROB and high ROB. This analysis showed that our findings were
robust and not dependent on any single study. Pooled effect esti-
mates for high psychosocial job strain varied between 1.31
Fig. 2. Forest plot comparison: high psychosocial job strain vs low psychosocial job strain, outcome: PTB.
H.A. Adane, R. Iles, J.A. Boyle et al. Public Health 228 (2024) 65e72
69
(1.21e1.43) and 1.35 (1.23e1.47) after the deletion of a single study
(see Table 3).
Discussion
This systematic review and meta-analysis identified two key
findings on the association between psychosocial work factors and
PTB. Firstly, there is moderate evidence suggesting that psychoso-
cial job strain is associated with an increased likelihood of PTB,
which leads to practical recommendation. Employers can support
them with flexible hours and a conducive work environment. Cli-
nicians should assess pregnant women for psychosocial job strain
during prenatal care. Policy makers should also develop and
implement workplace policies and procedures. A meta-analysis of
observational studies found that women with high job strain were
32% more likely to experience PTB, compared to women with low
job strain. Secondly, the review identified gaps in the evidence
regarding the relationship between psychosocial work factors and
PTB. These findings highlight the need for future research on the
relationship of psychosocial work factors to preterm birth.
There are three potential explanations for the relationship be-
tween high psychosocial job strain and PTB. First, high psychosocial
job strain can lead to increased production of catecholamines,
38
which can increase the risk of hypertension.
39
Hypertension, in
turn, can lead to an increase in uterine contractility, which can
contribute to PTB.
40,41
Second, high psychosocial job strain can in-
crease the likelihood of smoking.
42e44
Smoking can cause abnor-
malities or insufficiencies in the umbilical cord and placenta,
45e47
which can also contribute to PTB.
48e50
Third, women working in
high-strain jobs may also face other risks, such as physical occupa-
tional risks, sociodemographic factors (e.g., ethnicity, age, education),
and medical, lifestyle, or environmental factors.
51e54
For example,
women with high job strain may also have lower incomes compared
to those with low job strain.
55,56
This income disparity can affect a
number of factors that influence maternal and neonatal health,
57e59
such as access to healthcare services, nutrition, education, housing,
and living condition.
60e62
These factors, which are not typically
considered confounders in some studies, may increase the risk of
PTB.
16,19,35,36
This systematic review and meta-analysis found limited global
research on the association between high psychosocial job strain
and PTB. Only 10 studies were from high-income
countries
16e19,32e37
and none from low-income countries. The
studies included in this review are outdated, having been published
in the early 21st century and conducted data collection in the late
20th century.
16,19,32,33,35,36
As a result, they may not reflect the
current working conditions, such as changes in the nature of jobs,
alterations in occupational exposures, the growing number of
women in the workforce, and advancements in maternal health-
care services. Additionally, PTB rates have changed in 38 countries
since 2000, with 26 countries experiencing increases and 12
countries experiencing decreases.
63
Furthermore, although the
studies in this systematic review provide evidence linking high
psychosocial job strain to PTB, they have several methodological
shortcomings. These include the failure to adjust for confounding
factors,
16
the possibility of recall bias,
17,36,37
discrepancies in how
exposure is defined and measured, and misclassification of expo-
sure.
18,19,33
Workplace stress can increase the risk of PTB in preg-
nant women.
64,65
This review identified only the relationship
between psychosocial job strain and PTB,
16e19,32e37
but other types
of psychosocial work factors, such as bullying, sexual harassment,
inadequate reward and recognition, and poor organizational
management, may also be harmful. More research is needed to
understand the relationship between these other types of psy-
chosocial work factors and PTB.
The findings of this study indicate that pregnant women should
be aware of the risks of psychosocial job strain and take steps to
reduce their stress levels. This evidence should be incorporated into
existing policies to support the effective management of pregnant
working women. Maternal and child healthcare providers should
be knowledgeable about the risks of psychosocial job strain on
pregnancy. It is also crucial for future researchers to investigate
whether existing policies align with the current evidence regarding
the relationship between the most prevalent occupational expo-
sure and PTB. Additionally, further exploration of knowledge,
practice, and attitudes of healthcare providers regarding the effect
of occupational exposure on pregnancy and the implementation of
policy for pregnant women is warranted. This systematic review
and meta-analysis used rigorous methodological standards. Such as
the use of a well-established ROB assessment tool and the appli-
cation of the GRADE approach to evaluate evidence quality. The
systematic review has several limitations. First, it was limited to
English-language studies, which may have excluded relevant
studies from noneEnglish-speaking countries. Second, all of the
studies were observational and relied on self-reported data to
assess psychosocial job strain, which can be biased. Third, the
studies were all from high-income countries, which may limit the
generalizability of the findings to other countries.
Conclusion
This systematic review and meta-analysis found moderate evi-
dence of a statistically significant association between psychosocial
job strain and PTB. Thus, it is recommended that employers and
Table 2
Sub-group analysis of the effect of high psychosocial job strain on preterm birth.
Variables Categories Included studies (n) OR with (95% CI) I
2
,P-value
Study design Caseecontrol 3 1.38 (1.16e1.64) 0.0%, 0.48
Cross-sectional 2 1.30 (1.18e1.44) 0.0%, 0.33
Cohort 3 1.37 (1.02e1.83) 0.0%, 0.98
Publication year 2010 and above 3 1.37 (1.02e1.83) 0.0%, 0.98
Before 2010 5 1.32 (1.21e1.44) 0.0%, 0.60
Sample size 1000 2 1.31 (1.20e1.42) 0.0%, 0.96
<1000 6 1.62 (1.16e2.25) 0.0%, 0.60
Overall 8 1.32 (1.22e1.44) 0.0%, 0.90
Table 3
Sensitivity analysis of pooled estimate of preterm birth for high psychosocial job
strain.
Study omitted Effect estimate 95% CI
Brett et al. (1997)
36
1.31 1.21e1.43
Croteau et al. (2007)
37
1.33 1.22e1.45
Meyer et al. (2007)
19
1.32 1.16e1.50
Henriksen et al. (2010)
32
1.33 1.22e1.44
Vrijkotte et al. (2021)
34
1.32 1.22e1.44
Ceron-Mireles et al. (1996)
16
1.35 1.23e1.47
Escriba-Aguir et al. (2001)
17
1.32 1.21e1.43
Larsen et al. (2013)
18
1.32 1.21e1.44
H.A. Adane, R. Iles, J.A. Boyle et al. Public Health 228 (2024) 65e72
70
occupational health and safety authorities take measures to reduce
exposure of pregnant women to high psychosocial job strain.
Author statements
Ethical approval
None required.
Funding
This study was not externally funded. However, AC is
supported by an Australian Research Council Future Fellowship
(FT190100218), and HAA is the recipient of a Monash graduate
scholarship.
Competing interests
None declared.
Appendix A. Supplementary data
Supplementary data to this article can be found online at
https://doi.org/10.1016/j.puhe.2023.12.002.
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